How Hair Grows: Anagen, Catagen, Telogen & Exogen Hair Phases

How Hair Grows: Anagen, Catagen, Telogen & Exogen Hair Phases

Ever wondered what’s really happening on your scalp? Hair doesn’t just grow—it cycles. In this edition of Hair Loss 101, we break down the science behind the four distinct stages of hair growth and why understanding them is essential to managing hair thinning or loss.

Summary

  • The hair growth cycle has four phases: anagen (growth), catagen (transition), telogen (rest), and exogen (shedding).
  • Each phase plays a vital role in hair density, thickness, and overall appearance.
  • Gro Clinics takes a science-led approach to assess your cycle and develop tailored hair restoration plans.

The Hair Growth Cycle Explained

Anagen Phase (Growth)

This is the active growth phase, where hair follicles produce new hair. It can last anywhere from 2 to 7 years depending on genetic and hormonal factors. The longer this phase lasts, the longer your hair can grow.

Catagen Phase (Transition)

This short 2–3 week phase marks the end of active growth. The follicle detaches from its blood supply and begins to shrink. Around 3–5% of hairs are in this phase at any one time.

Telogen Phase (Rest)

During this 3-month phase, the follicle is dormant while the existing hair remains anchored. Roughly 10–15% of scalp hairs are in telogen at any given time.

Exogen Phase (Shedding)

This is when the resting hair is released and falls out, making way for new anagen hairs. Losing 50–100 hairs a day is typical and part of the natural renewal cycle.

Why the Hair Growth Cycle Matters for Hair Loss Treatment

Understanding the timing and balance of these phases is crucial for accurate diagnosis and treatment planning. A disruption—such as too many follicles entering telogen—can lead to visible thinning or shedding.

Treatments are often designed to support longer growth phases and reduce excessive shedding. This is why individualised plans based on your hair cycle are more effective than one-size-fits-all solutions.

Gro Clinics’ Approach: Tailored by Science

Gro Clinics uses clinical assessment and education to help you understand how your unique cycle affects your hair density and growth patterns.

  • In-depth consultations: We examine your hair density, shedding pattern, and medical history.
  • Evidence-based planning: Whether it's a hair transplant, growth factor therapy, or other treatment, your plan is based on your scalp’s biology.
  • Long-term support: Our goal is to help restore hair health with realistic expectations and ongoing guidance.

Clinics Across Australia and New Zealand

We offer consultations at our hair transplant clinics in:

Ready to find out what phase your hair is in? Book a consultation or call us on 1300 787 563 to get started.

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Hair Loss 101: Understanding the Norwood Hair Loss Scale
Your Hair Transplant Timeline: What to Expect Before, During and After